Hi Alexander,

You can use the HitTest method for this purpose - take a look at the following code snippet:

  private void Form1_Load(object sender, EventArgs e)
  {
   NChart chart = nChartControl1.Charts[0];

   NBarSeries bar = new NBarSeries();
   bar.Values.Add(10);
   bar.Values.Add(20);
   bar.Values.Add(30);
   chart.Series.Add(bar);

   nChartControl1.MouseDown += new MouseEventHandler(nChartControl1_MouseDown);
  }

  void nChartControl1_MouseDown(object sender, MouseEventArgs e)
  {
   NHitTestResult result = nChartControl1.HitTest(e.X, e.Y);

   if (result.ChartElement == ChartElement.DataPoint)
   {
    double value = (double)(((NSeries)result.Series).Values[result.DataPointIndex]);
    textBox1.Text = "Data Point [" + result.DataPointIndex.ToString() + "], Value [" + value.ToString() + "]";
   }
  }

it shows how to perform hit test and get the data point value when you click on it. Hope this helps - let us know if you meet any problems.